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Key Largo, FL, United States

Thorson J.T.,National Oceanic and Atmospheric Administration | Scheuerell M.D.,National Oceanic and Atmospheric Administration | Semmens B.X.,University of California at San Diego | Pattengill-Semmens C.V.,Reef Environmental Education Foundation REEF
Ecology | Year: 2014

Managing natural populations and communities requires detailed information regarding demographic processes at large spatial and temporal scales. This combination is challenging for both traditional scientific surveys, which often operate at localized scales, and recent citizen science designs, which often provide data with few auxiliary information (i.e., no information about individual age or condition). We therefore combine citizen science data at large scales with the demographic resolution afforded by recently developed, site-structured demographic models. We apply this approach to categorical data generated from citizen science representing species density of two managed reef fishes in the Gulf of Mexico, and use a modified Dail-Madsen model to estimate demographic trends, habitat associations, and interannual variability in recruitment. This approach identifies strong preferences for artificial structure for the recovering Goliath grouper, while revealing little evidence of either habitat associations or trends in abundance for mutton snapper. Results are also contrasted with a typical generalized linear mixed-model (GLMM) approach, using real-world and simulated data, to demonstrate the importance of accounting for the statistical complexities implied by spatially structured citizen science data. We conclude by discussing the increasing potential for synthesizing demographic models and citizen science data, and the management benefits that can be accrued. © 2014 by the Ecological Society of America. Source


Heppell S.A.,Oregon State University | Semmens B.X.,University of California at San Diego | Archer S.K.,Oregon State University | Pattengill-Semmens C.V.,Reef Environmental Education Foundation REEF | And 4 more authors.
Biological Conservation | Year: 2012

Many spawning aggregations of marine fishes have been fished beyond the point of sustainability, leading to increased calls for protection through seasonal and/or site-specific fishery closures. Once a closure has been put in place, monitoring the aggregation is imperative in order to learn whether protection leads to the recovery of the population. Current methods for monitoring the status of spawning aggregations rely largely on counts, either subsample or census, usually combined with capturing a subset of the fish to assess individual traits such as length and weight. Handling fish during the spawning aggregation can be stressful for the fish, and can ultimately lead to decreased spawning success, increased susceptibility to predators, or increased mortality through capture trauma or infection. Here we present a novel analysis for monitoring fish on a spawning aggregation that does not require the capture and handling of fish. Following a recovering aggregation of Nassau grouper (. Epinephelus striatus) over seven spawning seasons, we show that length-distribution data can be collected by divers using a video-based system with parallel lasers calibrated to a specific distance apart, and subsequently use those data to monitor changes in the size distribution over time. We detected recruitment of new fish to the grouper spawning aggregation in the fourth year of monitoring. In addition to tracking size distribution trends over time, the length distribution information could be combined with an established length-weight regression and an estimate of total abundance to estimate spawning stock biomass. We qualitatively cross-validate this method with census data to evaluate its effectiveness in monitoring the recovery or decline of aggregating species that can be visually observed. © 2012 Elsevier Ltd. Source


Ruttenberg B.I.,National Oceanic and Atmospheric Administration | Jschofield P.,U.S. Geological Survey | Akins J.L.,Reef Environmental Education Foundation REEF | Acosta A.,Florida Fish And Wildlife Conservation Commission | And 4 more authors.
Bulletin of Marine Science | Year: 2012

Over the past decade, Indo-Pacific lionfishes, Pterois volitans (Linnaeus, 1758) and Pterois miles (Bennett, 1828), venomous members of the scorpionfish family (Scorpaenidae), have invaded and spread throughout much of the tropical and subtropical northwestern Atlantic Ocean and Caribbean Sea. These species are generalist predators of fishes and invertebrates with the potential to disrupt the ecology of the invaded range. Lionfishes have been present in low numbers along the east coast of Florida since the 1980s, but were not reported in the Florida Keys until 2009. We document the appearance and rapid spread of lionfishes in the Florida Keys using multiple long-term data sets that include both pre- and post-invasion sampling. Our results are the first to quantify the invasion of lionfishes in a new area using multiple independent, ongoing monitoring data sets, two of which have explicit estimates of sampling effort. Between 2009 and 2011, lionfish frequency of occurrence, abundance, and biomass increased rapidly, increasing three- to six-fold between 2010 and 2011 alone. In addition, individuals were detected on a variety of reef and non-reef habitats throughout the Florida Keys. Because lionfish occurrence, abundance, and impacts are expected to continue to increase throughout the region, monitoring programs like those used in this study will be essential to document ecosystem changes that may result from this invasion. © 2012 Rosenstiel School of Marine & Atmospheric Science of the University of Myami. Source


Scyphers S.B.,Northeastern University | Powers S.P.,Dauphin Island Sea Laboratory | Akins J.L.,Reef Environmental Education Foundation REEF | Drymon J.M.,Dauphin Island Sea Laboratory | And 5 more authors.
Conservation Letters | Year: 2015

Documenting and responding to species invasions requires innovative strategies that account for ecological and societal complexities. We used the recent expansion of Indo-Pacific lionfish (Pterois volitans/miles) throughout northern Gulf of Mexico coastal waters to evaluate the role of stakeholders in documenting and responding to a rapid marine invasion. We coupled an online survey of spearfishers and citizen science monitoring programs with traditional fishery-independent data sources and found that citizen observations documented lionfish 1-2 years earlier and more frequently than traditional reef fish monitoring programs. Citizen observations first documented lionfish in 2010 followed by rapid expansion and proliferation in 2011 (+367%). From the survey of spearfishers, we determined that diving experience and personal observations of lionfish strongly influenced perceived impacts, and these perceptions were powerful predictors of support for initiatives. Our study demonstrates the value of engaging citizens for assessing and responding to large-scale and time-sensitive conservation problems. © 2014 The Authors. Source


Archer S.K.,Oregon State University | Heppell S.A.,Oregon State University | Semmens B.X.,Reef Environmental Education Foundation REEF | Pattengill-Semmens C.V.,Reef Environmental Education Foundation REEF | And 3 more authors.
Current Zoology | Year: 2012

Nassau grouper Epinephelus striatus are a large bodied, top level predator that is ecologically important throughout the Caribbean. Although typically solitary, Nassau grouper form large annual spawning aggregations at predictable times in specific locations. In 2003, The Cayman Islands Marine Conservation Board established protection for a newly rediscovered Nassau grouper spawning aggregation on Little Cayman, British West Indies. The large size of this aggregation provides a unique opportunity to study the behavior of Nassau grouper on a relatively intact spawning aggregation. During non-spawning periods Nassau grouper display a reddish-brown-and-white barred coloration. However, while aggregating they exhibit three additional color phases: "bicolor", "dark", and "white belly". We video sampled the population on multiple days leading up to spawning across five spawning years. Divers focused a laser caliper equipped video camera on individual fish at the aggregation. We later analyzed the video to determine the length of the fish and record the color phase. Our observations show that the relative proportion of fish in the bicolor color phase increases significantly on the day leading up to the primary night of spawning. The increase in the proportion of the bicolor color phase from 0.05 early in the aggregation to 0.40 on the day of spawning suggests that this color phase conveys that a fish is behaviorally and physiologically prepared to spawn. Additionally, 82.7% of fish exhibiting dark or white belly coloration early in the aggregation period suggests that these color phases are not only shown by female fish as was previously posited. ©2012 Current Zoology. Source

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